"A large number of observers acknowledge that dream life is capable of extraordinary achievements — at any rate, in certain fields ("Memory")." - Sigmund Freud

And, finally, groups have never thirsted after
truth. They demand illusions, and cannot do without them. They constantly give what is unreal precedence
over what is real; they are almost as strongly influenced
by what is untrue as by what is true. They
have an evident tendency not to distinguish between
the two.

Quite often they are lines of thought starting out from more than one centre, but not without their points of contact; almost invariably one train of thought is accompanied by its contradictory opposite, associatively linked to it by contrast.

Beauty has no obvious use; nor is there any clear cultural necessity for it. Yet civilization could not do without it.